The Experts below are selected from a list of 7218 Experts worldwide ranked by ideXlab platform
D L Atherton - One of the best experts on this subject based on the ideXlab platform.
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characterization of the magnetic easy axis in Pipeline Steel using magnetic barkhausen noise
Journal of Applied Physics, 1994Co-Authors: T W Krause, L Clapham, D L AthertonAbstract:The angular dependence of magnetic Barkhausen noise (MBN) on eight surfaces through the thickness of a 2% Mn Steel Pipeline sample was investigated. The MBN signal was analyzed by integrating the square of the MBN voltage signal with respect to the time axis. The resulting value, referred to as the MBN energy signal, was modeled by considering the irreversible motion of 180° domain walls, under the influence of an oriented magnetic field. An expression for the angular dependence of the MBN energy signal was derived and was given by energy=α cos2 θ+β, where α and β are the fitting parameters and θ is the angle between the maximum MBN signal and the applied sweep field. The α parameter was associated with the irreversible motion of 180° walls that contributed to the net macroscopic easy axis near the surface of the sample, while the β parameter was associated with the isotropic background MBN signal. The energy equation could be used to fit the data for all sweep field amplitudes in which the MBN spectrum w...
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characterization of the magnetic easy axis in Pipeline Steel using magnetic barkhausen noise
Journal of Applied Physics, 1994Co-Authors: T W Krause, L Clapham, D L AthertonAbstract:The angular dependence of magnetic Barkhausen noise (MBN) on eight surfaces through the thickness of a 2% Mn Steel Pipeline sample was investigated. The MBN signal was analyzed by integrating the square of the MBN voltage signal with respect to the time axis. The resulting value, referred to as the MBN energy signal, was modeled by considering the irreversible motion of 180° domain walls, under the influence of an oriented magnetic field. An expression for the angular dependence of the MBN energy signal was derived and was given by energy=α cos2 θ+β, where α and β are the fitting parameters and θ is the angle between the maximum MBN signal and the applied sweep field. The α parameter was associated with the irreversible motion of 180° walls that contributed to the net macroscopic easy axis near the surface of the sample, while the β parameter was associated with the isotropic background MBN signal. The energy equation could be used to fit the data for all sweep field amplitudes in which the MBN spectrum was observed. A dependence of the α and β parameters on the applied sweep field amplitude was observed.
Frank Y Cheng - One of the best experts on this subject based on the ideXlab platform.
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buckling resistance of an x80 Steel Pipeline at corrosion defect under bending moment
Journal of Natural Gas Science and Engineering, 2021Co-Authors: Yi Shuai, Xinhua Wang, Frank Y ChengAbstract:Abstract This work investigated the resistance of a corroded X80 Steel pipe to local buckling at a corrosion defect under bending moment. A nonlinear finite element model was developed to study buckling behavior of the pipe and determine critical bending moment. Parametric effects, including geometry of the corrosion defect (shape, depth, length and width), pipe geometry (pipe outer diameter and wall thickness) and operating pressure, were determined. Results show that Pipeline buckling at the corrosion defect depends on the defect geometry. A rectangular corrosion feature results in a lower buckling resistance than a semispherical corrosion pit or a cylindrical grooved corrosion. The depth and width of the corrosion defect are primarily factors affecting the buckling resistance, while the effect of defect length is negligible. The critical bending moment to cause buckling of the pipe, i.e., the critical buckling moment, decreases as the defect depth and width increase. The buckling resistance of the corroded pipe can be improved by increasing the pipe outer diameter and wall thickness. The role of internal pressure in buckling resistance depends on whether a constraint condition is applied at both ends of the pipe. For buried Pipelines without sealing ends, the critical buckling moment decreases as the internal pressure increases.
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modeling of mechanical behavior of corroded x80 Steel Pipeline reinforced with type b repair sleeve
Thin-walled Structures, 2021Co-Authors: Yi Shuai, Xinhua Wang, Junqiang Wang, Henggang Yin, Frank Y ChengAbstract:Abstract This work investigated stress response of a corroded X80 Steel Pipeline repaired by a type-B sleeve to internal pressure by finite element modeling. Firstly, a three-dimensional numerical model of corroded Pipeline reinforced with type-B sleeve was developed, and its accuracy and reliability were verified by the burst test results and the theoretical analytical solution, respectively. Second, the von Mises stress of the pipe body, sleeve and fillet weld was simulated under various affecting factors, i.e., internal pressure, corrosion defect dimension (depth, length and width) and sleeve length. Finally, a parameter sensitivity study was conducted to determine the effects of corrosion geometry and sleeve length on the repair efficiency. The main investigation results show that the type-B sleeve repair method is effective to restore the pressure-bearing capacity of the Pipeline at the corrosion defect, and the burst failure of repaired Pipeline always occurs at the region far away from the defect and sleeve. At the limit state of burst, the local defective region shows the highest stress, followed by the fillet weld, and the repair sleeve has the smallest stress, thus the maximum equivalent stress of the corroded zone is suggested to be used for measuring the repair efficiency of the repaired pipe by type-B sleeve. The sleeve-repair effectiveness is affected by depth of the corrosion defect, a deep corrosion defect reduces the performance of the sleeve repair compared with a shallow defect. The effect of the corrosion defect length on sleeve repair depends on the defect depth. Furthermore, there exist a critical length of the defect that affect the repair efficiency. The corrosion defect width shows limited effect on stress level at the defect of the repaired pipe. At last, a new method based on stress analysis is proposed to optimize the sleeve length for repairing a corroded Pipeline.
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the influence of cathodic protection potential on the biofilm formation and corrosion behaviour of an x70 Steel Pipeline in sulfate reducing bacteria media
Journal of Alloys and Compounds, 2017Co-Authors: Tao Liu, Frank Y ChengAbstract:Abstract This work investigated the biofilm formation and microbiologically influenced corrosion (MIC) of a Pipeline Steel under cathodic protection (CP) in an extracted soil in solution with addition of sulfate reducing bacteria (SRB), Desulfovibrio desulfuricans . It was found that the application of CP did not affect the planktonic bacterial growth in the solution. The CP facilitated the bacterial attachment to the Steel in this system, and a layer of biofilm formed on the cathodically protected Steel, decreasing the CP effectiveness for corrosion protection. The CP potential of −850 mV vs. copper sulfate electrode (CSE) was not sufficient to protect the Steel from corrosion in SRB containing media. Despite a further negative shift of the CP potential to −1000 mV vs. CSE was effective to control uniform corrosion of the Steel, pitting corrosion still occurred under biofilm on the Steel.
Yi Shuai - One of the best experts on this subject based on the ideXlab platform.
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buckling resistance of an x80 Steel Pipeline at corrosion defect under bending moment
Journal of Natural Gas Science and Engineering, 2021Co-Authors: Yi Shuai, Xinhua Wang, Frank Y ChengAbstract:Abstract This work investigated the resistance of a corroded X80 Steel pipe to local buckling at a corrosion defect under bending moment. A nonlinear finite element model was developed to study buckling behavior of the pipe and determine critical bending moment. Parametric effects, including geometry of the corrosion defect (shape, depth, length and width), pipe geometry (pipe outer diameter and wall thickness) and operating pressure, were determined. Results show that Pipeline buckling at the corrosion defect depends on the defect geometry. A rectangular corrosion feature results in a lower buckling resistance than a semispherical corrosion pit or a cylindrical grooved corrosion. The depth and width of the corrosion defect are primarily factors affecting the buckling resistance, while the effect of defect length is negligible. The critical bending moment to cause buckling of the pipe, i.e., the critical buckling moment, decreases as the defect depth and width increase. The buckling resistance of the corroded pipe can be improved by increasing the pipe outer diameter and wall thickness. The role of internal pressure in buckling resistance depends on whether a constraint condition is applied at both ends of the pipe. For buried Pipelines without sealing ends, the critical buckling moment decreases as the internal pressure increases.
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modeling of mechanical behavior of corroded x80 Steel Pipeline reinforced with type b repair sleeve
Thin-walled Structures, 2021Co-Authors: Yi Shuai, Xinhua Wang, Junqiang Wang, Henggang Yin, Frank Y ChengAbstract:Abstract This work investigated stress response of a corroded X80 Steel Pipeline repaired by a type-B sleeve to internal pressure by finite element modeling. Firstly, a three-dimensional numerical model of corroded Pipeline reinforced with type-B sleeve was developed, and its accuracy and reliability were verified by the burst test results and the theoretical analytical solution, respectively. Second, the von Mises stress of the pipe body, sleeve and fillet weld was simulated under various affecting factors, i.e., internal pressure, corrosion defect dimension (depth, length and width) and sleeve length. Finally, a parameter sensitivity study was conducted to determine the effects of corrosion geometry and sleeve length on the repair efficiency. The main investigation results show that the type-B sleeve repair method is effective to restore the pressure-bearing capacity of the Pipeline at the corrosion defect, and the burst failure of repaired Pipeline always occurs at the region far away from the defect and sleeve. At the limit state of burst, the local defective region shows the highest stress, followed by the fillet weld, and the repair sleeve has the smallest stress, thus the maximum equivalent stress of the corroded zone is suggested to be used for measuring the repair efficiency of the repaired pipe by type-B sleeve. The sleeve-repair effectiveness is affected by depth of the corrosion defect, a deep corrosion defect reduces the performance of the sleeve repair compared with a shallow defect. The effect of the corrosion defect length on sleeve repair depends on the defect depth. Furthermore, there exist a critical length of the defect that affect the repair efficiency. The corrosion defect width shows limited effect on stress level at the defect of the repaired pipe. At last, a new method based on stress analysis is proposed to optimize the sleeve length for repairing a corroded Pipeline.
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experimental and numerical investigation of the strain response of a dented api 5l x52 Pipeline subjected to continuously increasing internal pressure
Journal of Natural Gas Science and Engineering, 2018Co-Authors: Yi Shuai, Jian Shuai, Xiao ZhangAbstract:Abstract A dent is a common type of defect that occurs during Pipeline service. A dented region on a pipe usually creates a strong stress concentration that may become a threat to the safety and integrity of the Pipeline. Therefore, such issues are major concerns for Pipeline managers. To investigate the strain history behaviour of a dented Steel Pipeline subjected to increasing internal pressure, a full-scale experimental burst test was performed, and a nonlinear finite element method was used to compare the numerical and experimental results in this study. The paper first discusses the test specimens and test results. Then, the finite element numerical results are verified using the experimental measurement results. Subsequently, the strain behaviour at measurement points and the deformation behaviour of the test pipes were analysed in detail. Furthermore, a sensitivity analysis of strain in the axial and circumferential directions from the dent centre was performed. Deformation analysis reveal that an outward convex phenomenon occurred in axial shoulders on both sides of the dent when the Pipewall Yield Pressure reached. Test results and finite element analysis show that the strain in the dented regions changes rapidly and sharply with a large range, which can easily lead to fatigue under operation pressure for an unconstrained dent.
T W Krause - One of the best experts on this subject based on the ideXlab platform.
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characterization of the magnetic easy axis in Pipeline Steel using magnetic barkhausen noise
Journal of Applied Physics, 1994Co-Authors: T W Krause, L Clapham, D L AthertonAbstract:The angular dependence of magnetic Barkhausen noise (MBN) on eight surfaces through the thickness of a 2% Mn Steel Pipeline sample was investigated. The MBN signal was analyzed by integrating the square of the MBN voltage signal with respect to the time axis. The resulting value, referred to as the MBN energy signal, was modeled by considering the irreversible motion of 180° domain walls, under the influence of an oriented magnetic field. An expression for the angular dependence of the MBN energy signal was derived and was given by energy=α cos2 θ+β, where α and β are the fitting parameters and θ is the angle between the maximum MBN signal and the applied sweep field. The α parameter was associated with the irreversible motion of 180° walls that contributed to the net macroscopic easy axis near the surface of the sample, while the β parameter was associated with the isotropic background MBN signal. The energy equation could be used to fit the data for all sweep field amplitudes in which the MBN spectrum w...
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characterization of the magnetic easy axis in Pipeline Steel using magnetic barkhausen noise
Journal of Applied Physics, 1994Co-Authors: T W Krause, L Clapham, D L AthertonAbstract:The angular dependence of magnetic Barkhausen noise (MBN) on eight surfaces through the thickness of a 2% Mn Steel Pipeline sample was investigated. The MBN signal was analyzed by integrating the square of the MBN voltage signal with respect to the time axis. The resulting value, referred to as the MBN energy signal, was modeled by considering the irreversible motion of 180° domain walls, under the influence of an oriented magnetic field. An expression for the angular dependence of the MBN energy signal was derived and was given by energy=α cos2 θ+β, where α and β are the fitting parameters and θ is the angle between the maximum MBN signal and the applied sweep field. The α parameter was associated with the irreversible motion of 180° walls that contributed to the net macroscopic easy axis near the surface of the sample, while the β parameter was associated with the isotropic background MBN signal. The energy equation could be used to fit the data for all sweep field amplitudes in which the MBN spectrum was observed. A dependence of the α and β parameters on the applied sweep field amplitude was observed.
Jie Zhang - One of the best experts on this subject based on the ideXlab platform.
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damage evolution mechanism of buried Pipeline crossing reverse fault
Journal of Mechanical Science and Technology, 2021Co-Authors: Jie Zhang, Y Chen, B F Liang, B PanAbstract:Fault caused by earthquake is harmful to buried Pipelines. Long-distance transportation Pipelines will inevitably cross the seismic fault zones. In this paper, a numerical simulation model of X80 Pipeline under reverse faulting with a crossing angle of 60° was established. Damage evolution mechanism of buried Steel Pipeline was analyzed. Effects of internal pressure and diameter-thickness ratio on the stress, strain and displacement of Pipeline were discussed. The results show that the buckling phenomenon is more severe in the hanging wall than that in the footwall for reverse fault. For non-pressure Pipeline, local collapse occurs on the compression side. When the Pipeline wall buckles, the axial stress is released, and high-stress is mainly concentrated on the collapsed position. For pressure Pipeline, the internal pressure aggravates the buckling degree. Then, wrinkles appear on the compression side. The results can provide a reference for anti-seismic construction, repair and maintenance of buried Pipeline.
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mechanical behavior analysis of the buried Steel Pipeline crossing landslide area
Journal of Pressure Vessel Technology-transactions of The Asme, 2016Co-Authors: Jie Zhang, Zheng Liang, Chuanjun HanAbstract:Landslide movement is one of the threats for the structural integrity of buried Pipelines that are the main ways to transport oil and gas. In order to offer a theoretical basis for the design, safety evaluation and maintenance of Pipelines, mechanical behavior of the buried Steel Pipeline crossing landslide area was investigated by finite element method, considering Pipeline-soil interaction. Effects of landslide soil parameters, Pipeline parameters and landslide scale on the mechanical behavior of the buried Pipeline were discussed. The results show that there are three high stress areas on the buried Pipeline sections where the bending deformation are bigger. High stress area of the compression side is bigger than it on the tensile side, and the tensile strain is bigger than the compression strain in the deformation process. Buried Pipeline in the landslide bed with hard soil is prone to fracture. Bigger deformations appear on the Pipeline sections that the inside and outside lengths of the interface are 30m and 10m respectively. The maximum displacement of the Pipeline is smaller than the landslide displacement for the surrounding soil's deformation. Bending deformations and tensile strain of the Pipeline increase with the landslide displacement increases. Bending deformation and the maximum tensile strain of the Pipeline increase with increasing of the soil's elasticity modulus, cohesion and Pipeline's diameter-thickness ratio. Soil's Poisson's ratio has a great effect on the displacement of the middle part, but it has a little effect on other sections' displacement.
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Mechanical behaviour analysis of a buried Steel Pipeline under ground overload
Engineering Failure Analysis, 2016Co-Authors: Jie Zhang, Zheng Liang, Guanghui ZhaoAbstract:Abstract Ground overload is one of the most important factors that threaten the safe operations of oil and gas Pipelines. The mechanical behaviour of a buried Pipeline under ground overload was investigated using the finite element method in this paper. The effects of the overload parameters, Pipeline parameters and surrounding soil parameters on the stress–strain response of the buried Pipeline were discussed. The results show that the maximum von Mises stress appears on the top of the buried Pipeline under the loading area when the ground load is small, and the stress distribution is oval. As the ground load increases, the maximum stress increases, and the high stress area extends. The von Mises stress, plastic strain, plastic area size, settlement and ovality of the buried Pipeline increase as the ground load and loading area increase. The buckling phenomenon of the no-pressure buried Pipeline is more serious than the pressure Pipeline. As the internal pressure increases, the high stress area and the maximum plastic strain of the buried Pipeline first decrease and then increase, the settlement of the buried Pipeline increases, and the ovality decreases. The von Mises stress, maximum plastic strain, settlement and ovality of the buried Pipeline decrease with increasing buried depth, the surrounding soil's elasticity modulus, Poisson's ratio and cohesion. The maximum von Mises stress, high stress area, the maximum plastic strain, plastic area and ovality increase as the diameter–thickness ratio increases. The critical diameter–thickness ratio is 60, and the settlement of the buried Pipeline first increases and then decreases as the diameter–thickness ratio increases. Finally, a protective device of the buried Pipeline is designed for preventing ground overload. It can be repaired in a timely manner without stopping the transmission of oil and gas and widely used in different locations because of its simple structure and convenient installation.
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Numerical simulation of buckling behavior of the buried Steel Pipeline under reverse fault displacement
Mechanical Sciences, 2015Co-Authors: Jie Zhang, Zheng Liang, Chuanjun Han, Han ZhangAbstract:Abstract. Reverse fault movement is one of the threats for the structural integrity of buried oil-gas Pipelines caused by earthquakes. Buckling behavior of the buried Pipeline was investigated by finite element method. Effects of fault displacement, internal pressure, diameter-thick ratio, buried depth and friction coefficient on buckling behavior of the buried Steel Pipeline were discussed. The results show that internal pressure is the most important factor that affecting the Pipeline buckling pattern. Buckling mode of non-pressure Pipeline is collapse under reverse fault. Wrinkles appear on buried pressure Pipeline when the internal pressure is more than 0.4 Pmax. Four buckling locations appear on the buried pressure Pipeline under bigger fault displacement. There is only one wrinkle on the three locations of the Pipeline in the rising formation, but more wrinkles on the fourth location. Number of the wrinkle ridges and length of the wavy buckling increase with the increasing of friction coefficient. Number of buckling location decreases gradually with the decreasing of diameter-thick ratio. A protective device of buried Pipeline was designed for preventing Pipeline damage crossing fault area for its simple structure and convenient installation. Those results can be used to safety evaluation, maintenance and protection of buried Pipelines crossing fault area.
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numerical modeling of mechanical behavior for buried Steel Pipelines crossing subsidence strata
PLOS ONE, 2015Co-Authors: Jie Zhang, Zheng Liang, Chuanjun HanAbstract:This paper addresses the mechanical behavior of buried Steel Pipeline crossing subsidence strata. The investigation is based on numerical simulation of the nonlinear response of the Pipeline-soil system through finite element method, considering large strain and displacement, inelastic material behavior of buried Pipeline and the surrounding soil, as well as contact and friction on the Pipeline-soil interface. Effects of key parameters on the mechanical behavior of buried Pipeline were investigated, such as strata subsidence, diameter-thickness ratio, buried depth, internal pressure, friction coefficient and soil properties. The results show that the maximum strain appears on the outer transition subsidence section of the Pipeline, and its cross section is concave shaped. With the increasing of strata subsidence and diameter-thickness ratio, the out of roundness, longitudinal strain and equivalent plastic strain increase gradually. With the buried depth increasing, the deflection, out of roundness and strain of the Pipeline decrease. Internal pressure and friction coefficient have little effect on the deflection of buried Pipeline. Out of roundness is reduced and the strain is increased gradually with the increasing of internal pressure. The physical properties of soil have a great influence on the mechanical properties of buried Pipeline. The results from the present study can be used for the development of optimization design and preventive maintenance for buried Steel Pipelines.
